Sander



p 7, 955 w. P. HAMILTON 2,718,735

SANDER Filed y 7, 1952 2 Sheets-Sheet 1 Fig. l 7

William P. Hamil/on INVENTOR.

. 7a 7 74 WW 8M Sept. 27, 1955 w. P. HAMILTON SANDER 2 Sheets-Sheet 2 Filed July 7, 1952 William P. Hamilton w w w IN V EN TOR. m

-d Stew Patent f The present:invention relates to sanders and more particularly relates to a hand sander of the belt driven variety wherein the motor is mounted. within the sander frame or housing. V a It is an objectof the present invention to provide a noveldrive means from the motorto the endless belt rollers whereby the bulk ,of the sander is materially reduced. I

r It is another 'object of the .present invention to provide a hand sanding machine of the belt driven type which ,is provided with a novel hand-gripping means which is easily removablefrom the frame or housing of the'sander .to provide ready access to the interior of the machine andwhich further. permits the easy application of the sanding belt to the machine.

*Itis another object of the: invention, ancillary to the preceding object, toprovide a novelhand-gripping means for the sanding machine which gripping means serves the further function of'providing a shield or closure .for the open top vof the sander frame, o t otherg advantagesiof the present invention reside in its simple construction rendering it inexpensive to manufacture; and its compact1 1ess by incorporating the power unit -yvithin-the sander itself-whereby the sander is especially adaptable forlight finishing work.- 7 l These, togetherwith various ancillary'features and objects of the invention zwhich will later become -apparent'as the following description proceeds are attained by this device, a preferred embodiment of which is to be illustrated by wayof example only in the accompanying drawings; wherein: I

Figure 1- is a perspective viewof the hand sander of the present-invention in its. entirety. I

1 Figure 2' is atop view'ofthe sander of the present invention: with -t he combination -hand-grip and shield tsmq ta -;Figure -3 isa side-view of th sander of the present invention with the combination shield and hand-grip -31 1 w r Figure 4 is a sectional view of the sander taken substantially :along Tthef section line =44 of Figure f 1;

Figure 5 is a sectional view of the sander taken substantially along the section line 5-5 of Figure 4;

Figure 6"is a sectional view of a' portion of the sander showing the power plug-in'connection taken substantially along section line 6--6 of- Figure liand Figure 7 is a-sectional view of the spring loaded roller inountingmeans taken substantially along section line -7 7 o fFigure3.

l :Referring now more specifically to the accompanying diawings,-wherein like numerals designate similar parts throughout the various views, the numeral 10 designates the handsander in its--entirety.-

The sander ltl'eomprises generally a housing 12 and a oolnbir ation hand-grip and shield,. 14. The housing bi"frame"12"inc1t1ds'a bottom wallofbase 16"o'f generally rectangular shape and upstanding side walls 18 and 20 in the shape of parallelograms. It is to be noted 2,718,735 Patented; Sept, 27, t 1955 "ice that the housing or frame 12 may be of. one-piece construction and cast from any convenient metal. It is also to be noted that the housing or frame 12 has an open top 22 and ends 24 and 26 to provide easy access into the interior of the housing. a t

Shaft 28 is rotatably journaled in apertures 30 in the sides walls 18 and 20 of the housing adjacent the lower corner of the housing at open end 26 and extends transversely of the housing. A driving roller 32 of a relatively large diameter is carried by the shaft 28. At the upper corner of the housing adjacent open end 26, shaft 34 extends transversely of the housing and isrotatably journaled in the apertures 36 in the side walls of-the housing. Idler roller 38 of a diameterrelatively smaller than that of the driving roller 32 is carried by the shaft 34 and is rotatable therewith. i W

At the other open end of the housing, the side walls of the housing are longitudinallyslotted at 40 and a transverse shaft 42 is rotatably and slidingly seated in the slots and carried by shaft 42.between its ends is tensioning roller 44. Springs 46 are disposed in slots 40 and are guidingly retained therein by pins 48 extending from the inner ends of the slots. .The coil springs 46 have their inner ends ,disposedvagainst the inner end of slots 40 and have their outer ends pressing aga inst shaft 42 to spring load the roller 44 and normally urge the roller 44 away from the housing through the ,open end 24. At the lower corner of the housing adjacent the open end 24 thereof shaft 50 extends transversely of the housing and is rotatably journaled in apertures 52 in the side walls of the housing. Idlerlroller 54 is carried by shaft 50 and isjof approximatelyithesame diameter as idler roller 38 carried by shaft 34. Entrained around the rollers .32, 38, 44 and 54 is an endless sanding belt 56 which is adapted to bedriven in one direction by driving roller 32 t s Mounted on the base 16 of the sander 10 is an electric motor 58 which extends axially within the housing. Drive shaft 60 extends from one end of the motor toward the open end 26 of the housing and a bevel gear 62 is fixedly mounted on the end of the drive shaft. w Driven shaft 64 extends transversely ofthe housing and is journaled in apertures 66 of the housing side walls between shafts 34 and 28. Intermediate the ends of the shaft 64 is mounted a bevel gear 68 which meshes with the bevel gear 62 on the drive shaft 60 wherebyrot ation Ofllhfii. drive shaft will rotate thedriven shaft. Adjacent the ends ofshaft 64 and fixedly secured thereto are rollers 70 which frictionally contact driving roller.32 to impart rotary movement thereto upon rotation of th-e drive shaft 60. In this connection, it is noted that rollers 70 may be provided with anti-slipsurfaces to prevent slippage between the drivingroller -32;an d therollers 70 when the motor 58 is energized to rotate the drive shaft 60;. 1 1

To 'providemeans for energizing the electric motor 58, the side wall 20 of the housing. is provided. with plug-in socket 72 in which plug 74 carrying current from a source (not shown) through conductor 76 is;seate d Insulating bushings 78 insulate the 'plug-inconnection from the side walls of the housing. Conductor 80 carries the current to the switch terminal 82 on the side Wall 20 of the housing andthence t0. the motor 58, Switch 84 is operatively connected to the switch terminals 82'to open and close the circuit and thereby ener- .in;the opening 88 in the side wall 20 of the housing. 7

Wi Particular t f sn t s Fi ure and .5 pft e drawing, the construction and mounting of the handgrip and shield 14 will be made clearly apparent. The

hand-grip and shield 14 is of general channel-shaped construction and comprises generally a web'portion 90 and side flanges 92 and 94 respectively, which side flanges are recessed as at 96 to provide a hand-gripping portion for guiding the 'sander across a surface to be sanded. Each of theside flanges 92 and 94 of the hand-grip and shield 14 have'inturned edge flanges 98, the purpose of which will later become apparent. Further, the ends of the web portion 90 are arcuated or curved for a purpose which will also later become apparent.

The side walls'18 and 20 of the sander housing 12 are provided with longitudinally extending grooves 100 which open at the edges of the side walls adjacent the open'end 24 of the housing and which terminates inwardly of the open end 26 of the housing. To mount the hand-grip and shield 14 on the housing, the inturned edge flanges 98' of the hand-grip and shield are slidingly seated in the grooves 100 formed in the exterior surfaces of the side walls of the housing and when so seated, the web portion 90 of the hand-grip and shield covers the open top of the housing while the curved end portions of the web overlie a portion of the open ends 24 and 26 of the housing. Screws 102 extend through the side flanges 92 and 94 of the shield 14 and are threadedly received in apertures 104 of the housing side walls to fixedly maintain the hand-grip and shield on the housing. Further, the hand-grip and shield 14 is provided with openings 106 and 108 respectively in the side flange 92 to aiford communication with the exterior of the,

sander of switch 84 and plug-in sockets 72 respectively.

With further reference to the figures of the drawings, the operation of the device is as follows: When it is desired to place anew sanding belt on the machine, the hand-grip and shield 14 is detached from the housing 12 and the new sanding belt is entrained over the rollers of the housing and the hand-grip and shield is once again slid into position along the longitudinal grooves 100 of the side walls of the housing and fastened securely into place by the screws 102; the plug 74 is then inserted in its sockets 72 and the switch 84 actuated to close the circuit. Upon closing the circuit the motor 58 is energized, drive shaft 60 is rotated and driving roller 32 is in turn rotated whereby the sanding belt 56 is driven around the housing of the sander. Further, it is to be noted that removal of the shield 14 gives quick and ready access to the entire interior of the sander housing 12 to permit quick and simple repairs while the driving connection between the drive shaft and the driving roller is of a simple, compact and easily maintained linkage consisting of a minimum number of parts.

From the foregoing description, it is believed that the construction and operation of the sander will be clearly apparent to one skilled in theart and'further description is believed to be unnecessary. However, since numerous modifications andchanges will readily occur tothose'skill'ed in the'art after a consideration of the foregoing specification and accompanying'drawings, it is not desired to limit the invention to the exact construction shown and described, but all suitable modifications andequivalents may be resorted to falling within the scope of the appended claims.

Having described the invention, what is claimed as new is:

1. A hand sander comprising an elongated housing including a bottom and upstanding side walls, a motor mounted in said housing and a drive shaft extending from one end of said motor parallel to the longitudinal axis of said housing, shafts journaled at their ends in said sidewalls and extending transversely of said housing,rollers on said shafts, an endless belt entrained over said rollers, means operatively connecting one of said rollers with said drive shaft and a hand grip removably secured to the side walls of said housing, said connecting means including Jadriven shaft extending transversely of and drivingly connected to the drive shaft and disposed between the end of said drive shaft and one of the rollers, and a friction disc on said driven shaft engaging said one of said rollers.

2. A hand sander comprising an elongated housing including a base and upstanding side walls and having an open top and ends, a motor mounted in said housing and a drive shaft extending from one end of said motor parallel to the longitudinal axis of said housing, rollers journaled at the ends of said housing and extending transversely thereof, a sanding belt entrained over said rollers, means operatively connecting said drive shaft with one of said rollers, anda shield removably' secured to said side walls and covering the top of said housing and constituting a hand-grip for said sander, said connecting means including a driven shaft extending transversely of and drivingly connected to the drive shaft and disposed between the end of said drive shaft and one of the rollers, and a friction disc on said driven shaft engaging said one ofsaidrollers.

3. A hand sander comprising an elongated housing including a base and upstanding side walls and having an open top and ends, a motor mounted in said housing and a drive shaft extending from one end of said motor parallel to the longitudinal axis of said housing, rollers journaled at the ends of said housing and extending transversely thereof, a sanding belt entrained over said rollers, means operatively connecting said drive shaft with one of said rollers, and a shield removably secured to said side walls and covering the top of said housing and constituting a hand-grip for said sander, said shield comprising an elongated'channel shaped member including a web portion and depending side flanges having inturned longitudinal edge flanges thereon, said side walls having parallel, longitudinally extending grooves therein extending from one end of the housing, said shield flanges overlying said side walls and said edge flangesslidingl'y seating in said grooves and retaining said shield on said housing, an intermediate portion of each of said shield flanges being recessed to provide a hand gripping surface.

4. A hand sander comprising an elongated housing including a bottom and upstanding side walls, a motor mounted in said housing and a drive shaft extending from one end of said motor parallel to the longitudinal axis of said housing, shafts journaled at their ends in said side walls and extending transversely of said housing, rollers on said shafts, an endless belt entrained over said rollers, means operatively connecting one of said rollers with said drive shaft and a-hand grip removably secured to the side walls of said housing, said operatively connecting means comprising a bevel gear" mounted on the end of said drive shaft, adriven' shaft journaled in said side walls and'extending transversely of said-housing, a bevel gear on said driven shaft meshing with the drive shaft bevel gear and spaced-disks mounted-on said driven shaft engagingone of said rollers whereby' rotation of the drive shaft will be transmitted to the roller.

References Cited in the fileof this patent UNITED STATES PATENTS 1,332,123 Groves Feb. 24, 1920 1,412,365 Moulton Apr. 11, 1922 1,631,898 Swan June 7, 1927 1,920,364 Degen Aug. 1, 1933 2,280,762 Phipps Apr. 21, 1942 2,280,867 Swan Apr. 28, 1942 2,544,810 Strandberg ..,Mar. 13, 1951 2,576,745 Auten Nov. 27, 1951 2,590,913 Adams Apr. 1, 1952 2,621,453 Oren Dec. 16, 1952 FOREIGN PATENTS 602,436 Germany Sept. 8,1934

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